1. Field of the Invention
A wide variety of skin diseases are characterized by abnormal metabolic processes. Two classes of these conditions are the seborrheic dermatoses--which are typified by excessive secretion or disturbed quality of sebum, abnormal intercellular cement, and oily crusts or scales --and ichthyosiform dermatoses--which are typified by dry, scaly skin, abnormal thickening of epidermis, and rapid cell turnover in the skin. Specific diseases included in these broad categories include acne vulgaris (a seborrheic dermatosis) and psoriasis (an ichthyosiform dermatosis). Both of these conditions exhibit follicular keratin plugs. Other related conditions are ichthyosis vulgaris, senile hyperkeratosis, acanthosis, Derier's disease, keratoacanthomas, congenital ichthyosiform erythroderma, zosteriform keratosis, and lamellor ichthyosis.
Because these diseases appear on the skin and are unsightly, satisfactory agents should have relatively rapid action in the remission of the condition. In addition, the reagents should not affect the skin adversely and may not be toxic at the levels employed or the manner in which it is applied. Of particular interest, is an agent which can be taken internally, acting in a systemic manner in combatting the abnormal metabolic process.
Retinoic acid is found to be active in the remission of skin conditions, but has serious side effects. The retinoic acid when applied to the skin results in irritation and peeling of the skin, which is cosmetically undesirable. Because of the irritation, there is some discouragement of the user to employ the treatment.
2. Description of the Prior Art
U.S. Pat. No. 3,689,667 discloses the subject acid for promoting wound healing. Haeck et al, Rec. Trav. Chim. 85 (3), 334-8 (1966) reports the preparation of the subject acid. Redfearn, Arch. BioChem. BioPhys. 91 226-9 (1960) reports the C.sub.25 homologue has a curative action in the Vitamin A-deficient rat, and is converted into Vitamin A, unlike retinoic acid. U.S. Pat. No. 3,729,568 teaches the use of retinoic acid in the treatment of acne by providing for peeling.